Confirmation of the Unique Construction Techniques of Daraguk at Hapseong Seongsan Fortress

Green Light for Hupcheon Seongsan Fortress to be Designated as a Historic Site

Northeast section of Seongsan Fortress stone wall and the embankment below the stone wall [Image source=Hapcheon-gun]

[Asia Economy Yeongnam Reporting Headquarters Reporter Choi Soon-kyung] Hapcheon-gun, Gyeongnam Province, confirmed a unique Gaya-style fortress construction technique, distinctly different from Silla and Baekje, during the 7th investigation of Seongsan Fortress (Gyeongsangnam-do Monument No. 293), which is undergoing efforts for elevation to a national historic site.

The investigation was conducted by the Gyeongnam Research Institute on the 1st, where an academic advisory meeting was held at the excavation site with related experts and local residents to introduce the excavation results so far and discuss the justification for historic site designation.

Seongsan Fortress was constructed on an independent hill along the Hwanggang River, an ancient major transportation route.

Together with the adjacent Okjeon Tumuli Cluster, it is an important relic that can reveal the lifestyle, political development and progression of the Gaya period people, as well as ancient civil engineering techniques of Gaya. The construction period is estimated to be from the late 5th century to the early 6th century.

Seongsan Fortress was known to have natural fortress walls and moats on the west side facing the Hwanggang River, stone walls on the south and east sides, and earthen walls on the north side. However, the recent excavation revealed that the northeastern section was also constructed with stone walls.

The stone walls in the northeastern investigation section were built using a double-wall construction method (夾築式), stacking inner and outer walls together, with a width of 6 meters and a remaining height of about 1.8 meters.

The processing of the stones, the shape of the facing stones, the stone stacking technique, and the excavated artifacts clearly demonstrate the characteristics of Gaya period fortress walls. For the first time, a construction technique was confirmed where the foundation (the base structure below the main body of the fortress wall) was built in the same form as earthen walls.

In particular, when embanking the foundation below the stone wall (a technique of compacting soil layer by layer), wooden pillars called mokju were driven in to reinforce the structure, and an earthen embankment (toje) made of soil and stones was created. Then, soil was piled inwardly at a reverse slope, revealing a unique Gaya construction technique.

The stone walls in the northeastern section of this investigation replaced the stone core construction technique used in the previously investigated northwestern earthen walls with 6-meter-wide stone retaining walls. Notably, the transition from earthen walls to stone walls becomes more distinct toward the east and south of Seongsan Fortress, making this a very rare case of fortress construction.

A county official stated, “The academic excavation of Seongsan Fortress is being conducted with provincial support as part of the national project ‘Research and Maintenance of the Gaya Cultural Zone.’ We have confirmed the value and justification for designating Seongsan Fortress as a historic site through this investigation, and we will intensify efforts to have it elevated to a national historic site.”

This content was produced with the assistance of AI translation services.